sysdeps/ieee754/flt-32/s_asinhf.c

   1 /* s_asinhf.c -- float version of s_asinh.c.
   2  * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.
   3  */
   4
   5 /*
   6  * ====================================================
   7  * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
   8  *
   9  * Developed at SunPro, a Sun Microsystems, Inc. business.
  10  * Permission to use, copy, modify, and distribute this
  11  * software is freely granted, provided that this notice
  12  * is preserved.
  13  * ====================================================
  14  */
  15
  16 #include "math.h"
  17 #include "math_private.h"
  18
  19 static const float
  20 one =  1.0000000000e+00, /* 0x3F800000 */
  21 ln2 =  6.9314718246e-01, /* 0x3f317218 */
  22 huge=  1.0000000000e+30;
  23
  24 float
  25 __asinhf(float x)
  26 {
  27         float w;
  28         int32_t hx,ix;
  29         GET_FLOAT_WORD(hx,x);
  30         ix = hx&0x7fffffff;
  31         if(__builtin_expect(ix< 0x38000000, 0)) {       /* |x|<2**-14 */
  32             if(huge+x>one) return x;    /* return x inexact except 0 */
  33         }
  34         if(__builtin_expect(ix>0x47000000, 0)) {        /* |x| > 2**14 */
  35             if(ix>=0x7f800000) return x+x;      /* x is inf or NaN */
  36             w = __ieee754_logf(fabsf(x))+ln2;
  37         } else {
  38             float xa = fabsf(x);
  39             if (ix>0x40000000) {        /* 2**14 > |x| > 2.0 */
  40                 w = __ieee754_logf(2.0f*xa+one/(__ieee754_sqrtf(xa*xa+one)+xa));
  41             } else {            /* 2.0 > |x| > 2**-14 */
  42                 float t = xa*xa;
  43                 w =__log1pf(xa+t/(one+__ieee754_sqrtf(one+t)));
  44             }
  45         }
  46         return __copysignf(w, x);
  47 }
  48 weak_alias (__asinhf, asinhf)